lidavidm commented on a change in pull request #12739: URL: https://github.com/apache/arrow/pull/12739#discussion_r837682632
########## File path: docs/source/java/getstarted.rst ########## @@ -0,0 +1,31 @@ +.. Licensed to the Apache Software Foundation (ASF) under one +.. or more contributor license agreements. See the NOTICE file +.. distributed with this work for additional information +.. regarding copyright ownership. The ASF licenses this file +.. to you under the Apache License, Version 2.0 (the +.. "License"); you may not use this file except in compliance +.. with the License. You may obtain a copy of the License at + +.. http://www.apache.org/licenses/LICENSE-2.0 + +.. Unless required by applicable law or agreed to in writing, +.. software distributed under the License is distributed on an +.. "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +.. KIND, either express or implied. See the License for the +.. specific language governing permissions and limitations +.. under the License. + +.. default-domain:: java +.. highlight:: java + +.. _getstarted: + +=============== +Getting Started Review comment: I think it's fairly pointless to have a getting started page that just links to other pages. Let's move the main content back here. ########## File path: docs/source/java/quickstartguide.rst ########## @@ -0,0 +1,482 @@ +.. Licensed to the Apache Software Foundation (ASF) under one +.. or more contributor license agreements. See the NOTICE file +.. distributed with this work for additional information +.. regarding copyright ownership. The ASF licenses this file +.. to you under the Apache License, Version 2.0 (the +.. "License"); you may not use this file except in compliance +.. with the License. You may obtain a copy of the License at + +.. http://www.apache.org/licenses/LICENSE-2.0 + +.. Unless required by applicable law or agreed to in writing, +.. software distributed under the License is distributed on an +.. "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +.. KIND, either express or implied. See the License for the +.. specific language governing permissions and limitations +.. under the License. + +.. default-domain:: java +.. highlight:: java + +.. _java_quickstartguide: + +================= +Quick Start Guide +================= + +.. contents:: + +Arrow java manage data in Vector Schema Root (somewhat analogous to tables and record +batches in the other Arrow implementations). Before to create a Vector Schema Root let's +define another topics neededs for that purpose. + +Create A Value Vector +********************* + +It's called `array` in the columnar format specification. Represent a one-dimensional +sequence of homogeneous values. + +**Int Vector**: Create an value vector of int32s like this [1, null, 2] + +.. code-block:: Java + + import org.apache.arrow.memory.BufferAllocator; + import org.apache.arrow.memory.RootAllocator; + import org.apache.arrow.vector.IntVector; + + try(BufferAllocator rootAllocator = new RootAllocator(); + IntVector intVector = new IntVector("fixed-size-primitive-layout", rootAllocator)){ + intVector.allocateNew(3); + intVector.set(0,1); + intVector.setNull(1); + intVector.set(2,2); + intVector.setValueCount(3); + System.out.println("Vector created in memory: " + intVector); + } + +**Varchar Vector**: Create an value vector of string like this [one, two, three] + +.. code-block:: Java + + import org.apache.arrow.memory.BufferAllocator; + import org.apache.arrow.memory.RootAllocator; + import org.apache.arrow.vector.VarCharVector; + + try(BufferAllocator rootAllocator = new RootAllocator(); + VarCharVector varCharVector = new VarCharVector("variable-size-primitive-layout", rootAllocator)){ + varCharVector.allocateNew(3); + varCharVector.set(0, "one".getBytes()); + varCharVector.set(1, "two".getBytes()); + varCharVector.set(2, "three".getBytes()); + varCharVector.setValueCount(3); + System.out.println("Vector created in memory: " + varCharVector); + } + +Create A Field +************** + +Fields are used to denote the particular columns of tabular data. + +**Field**: Create a column "document" of string type with metadata. + +.. code-block:: Java + + import org.apache.arrow.vector.types.pojo.ArrowType; + import org.apache.arrow.vector.types.pojo.Field; + import org.apache.arrow.vector.types.pojo.FieldType; + + Map<String, String> metadata = new HashMap<>(); + metadata.put("A", "Id card"); + metadata.put("B", "Passport"); + metadata.put("C", "Visa"); + Field document = new Field("document", new FieldType(true, new ArrowType.Utf8(), /*dictionary*/ null, metadata), /*children*/ null); + +Create A Schema +*************** + +Schema holds a sequence of fields together with some optional metadata. + +**Schema**: Create a schema describing datasets with two columns: +a int32 column "A" and a utf8-encoded string column "B" + +.. code-block:: Java + + import org.apache.arrow.vector.types.pojo.ArrowType; + import org.apache.arrow.vector.types.pojo.Field; + import org.apache.arrow.vector.types.pojo.FieldType; + import org.apache.arrow.vector.types.pojo.Schema; + import static java.util.Arrays.asList; + + Map<String, String> metadata = new HashMap<>(); + metadata.put("K1", "V1"); + metadata.put("K2", "V2"); + Field a = new Field("A", FieldType.nullable(new ArrowType.Int(32, true)), null); + Field b = new Field("B", FieldType.nullable(new ArrowType.Utf8()), null); + Schema schema = new Schema(asList(a, b), metadata); + +Create A Vector Schema Root +*************************** + +VectorSchemaRoot is somewhat analogous to tables and record batches in the other +Arrow implementations. + +**VectorSchemaRoot**: Create a dataset with metadata that contains integer age and +string names of data. + +.. code-block:: Java + + import org.apache.arrow.memory.BufferAllocator; + import org.apache.arrow.memory.RootAllocator; + import org.apache.arrow.vector.IntVector; + import org.apache.arrow.vector.VarCharVector; + import org.apache.arrow.vector.VectorSchemaRoot; + import org.apache.arrow.vector.types.pojo.ArrowType; + import org.apache.arrow.vector.types.pojo.Field; + import org.apache.arrow.vector.types.pojo.FieldType; + import org.apache.arrow.vector.types.pojo.Schema; + + import java.nio.charset.StandardCharsets; + import java.util.HashMap; + import java.util.Map; + import static java.util.Arrays.asList; + + Map<String, String> metadataField = new HashMap<>(); + metadataField.put("K1-Field", "K1F1"); + metadataField.put("K2-Field", "K2F2"); + Field a = new Field("Column-A-Age", FieldType.nullable(new ArrowType.Int(32, true)), null); + Field b = new Field("Column-B-Name", new FieldType(true, new ArrowType.Utf8(), /*dictionary*/ null, metadataField), null); + Map<String, String> metadataSchema = new HashMap<>(); + metadataSchema.put("K1-Schema", "K1S1"); + metadataSchema.put("K2-Schema", "K2S2"); + Schema schema = new Schema(asList(a, b), metadataSchema); + System.out.println("Field A: " + a); + System.out.println("Field B: " + b + ", Metadata: " + b.getMetadata()); + System.out.println("Schema: " + schema); + try(BufferAllocator rootAllocator = new RootAllocator(); + VectorSchemaRoot vectorSchemaRoot = VectorSchemaRoot.create(schema, rootAllocator)){ + vectorSchemaRoot.setRowCount(3); + try(IntVector intVectorA = (IntVector) vectorSchemaRoot.getVector("Column-A-Age"); + VarCharVector varCharVectorB = (VarCharVector) vectorSchemaRoot.getVector("Column-B-Name")) { + intVectorA.allocateNew(3); + intVectorA.set(0, 10); + intVectorA.set(1, 20); + intVectorA.set(2, 30); + + varCharVectorB.allocateNew(3); + varCharVectorB.set(0, "Dave".getBytes(StandardCharsets.UTF_8)); + varCharVectorB.set(1, "Peter".getBytes(StandardCharsets.UTF_8)); + varCharVectorB.set(2, "Mary".getBytes(StandardCharsets.UTF_8)); + + System.out.println("Vector Schema Root: \n" + vectorSchemaRoot.contentToTSVString()); + } + } + +Create a IPC File or Random Access Format +***************************************** + +The Arrow Interprocess Communication (IPC) format defines two types of binary +formats for serializing Arrow data: the streaming format and the file format +(or random access format). Such files can be directly memory-mapped when read. + +**Write File or Random Access Format**: Write to a file a dataset with metadata +that contains integer age and string names of data. + +.. code-block:: Java + + import org.apache.arrow.memory.BufferAllocator; + import org.apache.arrow.memory.RootAllocator; + import org.apache.arrow.vector.IntVector; + import org.apache.arrow.vector.VarCharVector; + import org.apache.arrow.vector.VectorSchemaRoot; + import org.apache.arrow.vector.ipc.ArrowFileWriter; + import org.apache.arrow.vector.types.pojo.ArrowType; + import org.apache.arrow.vector.types.pojo.Field; + import org.apache.arrow.vector.types.pojo.FieldType; + import org.apache.arrow.vector.types.pojo.Schema; + + import java.io.File; + import java.io.FileOutputStream; + import java.io.IOException; + import java.nio.charset.StandardCharsets; + import java.util.HashMap; + import java.util.Map; + + import static java.util.Arrays.asList; + + Map<String, String> metadataField = new HashMap<>(); + metadataField.put("K1-Field", "K1F1"); + metadataField.put("K2-Field", "K2F2"); + Field a = new Field("Column-A-Age", FieldType.nullable(new ArrowType.Int(32, true)), null); + Field b = new Field("Column-B-Name", new FieldType(true, new ArrowType.Utf8(), /*dictionary*/ null, metadataField), null); + Map<String, String> metadataSchema = new HashMap<>(); + metadataSchema.put("K1-Schema", "K1S1"); + metadataSchema.put("K2-Schema", "K2S2"); + Schema schema = new Schema(asList(a, b), metadataSchema); + System.out.println("Field A: " + a); + System.out.println("Field B: " + b + ", Metadata: " + b.getMetadata()); + System.out.println("Schema: " + schema); + try(BufferAllocator rootAllocator = new RootAllocator(); + VectorSchemaRoot vectorSchemaRoot = VectorSchemaRoot.create(schema, rootAllocator)){ + vectorSchemaRoot.setRowCount(3); + try(IntVector intVectorA = (IntVector) vectorSchemaRoot.getVector("Column-A-Age"); + VarCharVector varCharVectorB = (VarCharVector) vectorSchemaRoot.getVector("Column-B-Name")) { + intVectorA.allocateNew(3); + intVectorA.set(0, 10); + intVectorA.set(1, 20); + intVectorA.set(2, 30); + varCharVectorB.allocateNew(3); + varCharVectorB.set(0, "Dave".getBytes(StandardCharsets.UTF_8)); + varCharVectorB.set(1, "Peter".getBytes(StandardCharsets.UTF_8)); + varCharVectorB.set(2, "Mary".getBytes(StandardCharsets.UTF_8)); + // Arrow Java At Rest + File file = new File("randon_access_to_file.arrow"); + try (FileOutputStream fileOutputStream = new FileOutputStream(file); + ArrowFileWriter writer = new ArrowFileWriter(vectorSchemaRoot, null, fileOutputStream.getChannel()) + ) { + writer.start(); + writer.writeBatch(); + writer.end(); + System.out.println("Record batches written: " + writer.getRecordBlocks().size() + ". Number of rows written: " + vectorSchemaRoot.getRowCount()); + } catch (IOException e) { + e.printStackTrace(); + } + } + } + +Create A Flight Server And Flight Client Review comment: IMO this section can be omitted, we can defer this for a dedicated page about Flight ########## File path: docs/source/java/quickstartguide.rst ########## @@ -0,0 +1,482 @@ +.. Licensed to the Apache Software Foundation (ASF) under one +.. or more contributor license agreements. See the NOTICE file +.. distributed with this work for additional information +.. regarding copyright ownership. The ASF licenses this file +.. to you under the Apache License, Version 2.0 (the +.. "License"); you may not use this file except in compliance +.. with the License. You may obtain a copy of the License at + +.. http://www.apache.org/licenses/LICENSE-2.0 + +.. Unless required by applicable law or agreed to in writing, +.. software distributed under the License is distributed on an +.. "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +.. KIND, either express or implied. See the License for the +.. specific language governing permissions and limitations +.. under the License. + +.. default-domain:: java +.. highlight:: java + +.. _java_quickstartguide: + +================= +Quick Start Guide +================= + +.. contents:: + +Arrow java manage data in Vector Schema Root (somewhat analogous to tables and record +batches in the other Arrow implementations). Before to create a Vector Schema Root let's +define another topics neededs for that purpose. + +Create A Value Vector +********************* + +It's called `array` in the columnar format specification. Represent a one-dimensional +sequence of homogeneous values. + +**Int Vector**: Create an value vector of int32s like this [1, null, 2] + +.. code-block:: Java + + import org.apache.arrow.memory.BufferAllocator; + import org.apache.arrow.memory.RootAllocator; + import org.apache.arrow.vector.IntVector; + + try(BufferAllocator rootAllocator = new RootAllocator(); + IntVector intVector = new IntVector("fixed-size-primitive-layout", rootAllocator)){ + intVector.allocateNew(3); + intVector.set(0,1); + intVector.setNull(1); + intVector.set(2,2); + intVector.setValueCount(3); + System.out.println("Vector created in memory: " + intVector); + } + +**Varchar Vector**: Create an value vector of string like this [one, two, three] + +.. code-block:: Java + + import org.apache.arrow.memory.BufferAllocator; + import org.apache.arrow.memory.RootAllocator; + import org.apache.arrow.vector.VarCharVector; + + try(BufferAllocator rootAllocator = new RootAllocator(); + VarCharVector varCharVector = new VarCharVector("variable-size-primitive-layout", rootAllocator)){ + varCharVector.allocateNew(3); + varCharVector.set(0, "one".getBytes()); + varCharVector.set(1, "two".getBytes()); + varCharVector.set(2, "three".getBytes()); + varCharVector.setValueCount(3); + System.out.println("Vector created in memory: " + varCharVector); + } + +Create A Field +************** + +Fields are used to denote the particular columns of tabular data. + +**Field**: Create a column "document" of string type with metadata. + +.. code-block:: Java + + import org.apache.arrow.vector.types.pojo.ArrowType; + import org.apache.arrow.vector.types.pojo.Field; + import org.apache.arrow.vector.types.pojo.FieldType; + + Map<String, String> metadata = new HashMap<>(); + metadata.put("A", "Id card"); + metadata.put("B", "Passport"); + metadata.put("C", "Visa"); + Field document = new Field("document", new FieldType(true, new ArrowType.Utf8(), /*dictionary*/ null, metadata), /*children*/ null); + +Create A Schema +*************** + +Schema holds a sequence of fields together with some optional metadata. + +**Schema**: Create a schema describing datasets with two columns: +a int32 column "A" and a utf8-encoded string column "B" + +.. code-block:: Java + + import org.apache.arrow.vector.types.pojo.ArrowType; + import org.apache.arrow.vector.types.pojo.Field; + import org.apache.arrow.vector.types.pojo.FieldType; + import org.apache.arrow.vector.types.pojo.Schema; + import static java.util.Arrays.asList; + + Map<String, String> metadata = new HashMap<>(); + metadata.put("K1", "V1"); + metadata.put("K2", "V2"); + Field a = new Field("A", FieldType.nullable(new ArrowType.Int(32, true)), null); + Field b = new Field("B", FieldType.nullable(new ArrowType.Utf8()), null); + Schema schema = new Schema(asList(a, b), metadata); + +Create A Vector Schema Root +*************************** + +VectorSchemaRoot is somewhat analogous to tables and record batches in the other +Arrow implementations. + +**VectorSchemaRoot**: Create a dataset with metadata that contains integer age and +string names of data. + +.. code-block:: Java + + import org.apache.arrow.memory.BufferAllocator; + import org.apache.arrow.memory.RootAllocator; + import org.apache.arrow.vector.IntVector; + import org.apache.arrow.vector.VarCharVector; + import org.apache.arrow.vector.VectorSchemaRoot; + import org.apache.arrow.vector.types.pojo.ArrowType; + import org.apache.arrow.vector.types.pojo.Field; + import org.apache.arrow.vector.types.pojo.FieldType; + import org.apache.arrow.vector.types.pojo.Schema; + + import java.nio.charset.StandardCharsets; + import java.util.HashMap; + import java.util.Map; + import static java.util.Arrays.asList; + + Map<String, String> metadataField = new HashMap<>(); + metadataField.put("K1-Field", "K1F1"); + metadataField.put("K2-Field", "K2F2"); + Field a = new Field("Column-A-Age", FieldType.nullable(new ArrowType.Int(32, true)), null); + Field b = new Field("Column-B-Name", new FieldType(true, new ArrowType.Utf8(), /*dictionary*/ null, metadataField), null); + Map<String, String> metadataSchema = new HashMap<>(); + metadataSchema.put("K1-Schema", "K1S1"); + metadataSchema.put("K2-Schema", "K2S2"); + Schema schema = new Schema(asList(a, b), metadataSchema); + System.out.println("Field A: " + a); + System.out.println("Field B: " + b + ", Metadata: " + b.getMetadata()); + System.out.println("Schema: " + schema); + try(BufferAllocator rootAllocator = new RootAllocator(); + VectorSchemaRoot vectorSchemaRoot = VectorSchemaRoot.create(schema, rootAllocator)){ + vectorSchemaRoot.setRowCount(3); + try(IntVector intVectorA = (IntVector) vectorSchemaRoot.getVector("Column-A-Age"); + VarCharVector varCharVectorB = (VarCharVector) vectorSchemaRoot.getVector("Column-B-Name")) { + intVectorA.allocateNew(3); + intVectorA.set(0, 10); + intVectorA.set(1, 20); + intVectorA.set(2, 30); + + varCharVectorB.allocateNew(3); + varCharVectorB.set(0, "Dave".getBytes(StandardCharsets.UTF_8)); + varCharVectorB.set(1, "Peter".getBytes(StandardCharsets.UTF_8)); + varCharVectorB.set(2, "Mary".getBytes(StandardCharsets.UTF_8)); + + System.out.println("Vector Schema Root: \n" + vectorSchemaRoot.contentToTSVString()); + } + } + +Create a IPC File or Random Access Format Review comment: Can we also have a section about reading a file? ########## File path: docs/source/java/modules.rst ########## @@ -0,0 +1,413 @@ +.. Licensed to the Apache Software Foundation (ASF) under one +.. or more contributor license agreements. See the NOTICE file +.. distributed with this work for additional information +.. regarding copyright ownership. The ASF licenses this file +.. to you under the Apache License, Version 2.0 (the +.. "License"); you may not use this file except in compliance +.. with the License. You may obtain a copy of the License at + +.. http://www.apache.org/licenses/LICENSE-2.0 + +.. Unless required by applicable law or agreed to in writing, +.. software distributed under the License is distributed on an +.. "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +.. KIND, either express or implied. See the License for the +.. specific language governing permissions and limitations +.. under the License. + +.. default-domain:: java +.. highlight:: java + +.. _java_modules: + +======= +Modules +======= + +.. contents:: + +This is the variety of arrow java documentation: + +* `Specification and protocols`_: This contains agnostic specification that is implemented in this case by arrow java modules. +* `Supported environment`_ (like this): This contains answers for what-is-that arrow java module. +* `Cookbook`_: This contains answers about how-to-use arrow java modules with practices examples. +* `Development`_: This contains detailed information about what you need to consider to start with arrow java development. + +Arrow java modules is created using specification such as columnar format, off-heap +memory, serialization and interprocess communication (IPC). Some of the java modules +was created with their own native implementations and others through bindings. + +.. list-table:: Arrow Java Implementations and Bindings + :widths: 25 75 + :header-rows: 1 + + * - Module + - Root Decision + * - Arrow Memory + - Native implementation. + * - Arrow Vector + - Native implementation. + * - Arrow Flight Grpc + - Native implementation. + * - Arrow Flight Sql + - Native implementation. + * - Arrow Algorithm + - Native implementation. + * - Arrow Compression + - Native implementation. + * - Arrow C Data Interface + - Native implementation. + * - Arrow Dataset + - Bindings + * - Arrow ORC + - Bindings + * - Arrow Gandiva + - Bindings + +Arrow java is divided in these modules to offer in-memory columnar data structures: + +.. list-table:: Arrow Java Modules + :widths: 25 75 + :header-rows: 1 + + * - Module + - Description + * - arrow-format + - Generated Java files from the IPC Flatbuffer definitions. + * - arrow-memory-core + - Core off-heap memory management libraries for Arrow ValueVectors. + * - arrow-memory-unsafe + - Allocator and utils for allocating memory in Arrow based on sun.misc.Unsafe. + * - arrow-memory-netty + - Netty allocator and utils for allocating memory in Arrow. + * - arrow-vector + - An off-heap reference implementation for Arrow columnar data format. + * - arrow-tools + - Java applications for working with Arrow ValueVectors. + * - arrow-jdbc + - (`Experimental`) A library for converting JDBC data to Arrow data. + * - arrow-plasma + - (`Experimental`) Java client for the Plasma object store. + * - flight-core + - (`Experimental`) An RPC mechanism for transferring ValueVectors. + * - flight-grpc + - (`Experimental`) Contains utility class to expose Flight gRPC service and client + * - flight-sql + - (`Experimental`) Contains utility classes to expose Flight SQL semantics for clients and servers over Arrow Flight. + * - flight-integration-tests + - Integration tests for Flight RPC. + * - arrow-performance + - JMH Performance benchmarks for other Arrow libraries. + * - arrow-algorithm + - (`Experimental`) A collection of algorithms for working with ValueVectors. + * - arrow-avro + - (`Experimental`) A library for converting Avro data to Arrow data. + * - arrow-compression + - (`Experimental`) A library for working with the compression/decompression of Arrow data. + * - arrow-c-data + - Java implementation of C Data Interface + * - arrow-orc + - (`Experimental`) A JNI wrapper for the C++ ORC reader implementation. + * - arrow-gandiva + - Java wrappers around the native Gandiva SQL expression compiler. + * - arrow-dataset + - Java implementation of Arrow Dataset API/Framework + +For more detail about how to install this modules please review +:doc:`Installing Java Modules <install>`. + +.. note:: + + Arrow java modules offer support to work data: (1) in-memory, + (2) at rest and (3) on-the-wire. + +Lets zoom-in arrow java modules to take advantage of this functionalities: + +Arrow Java In-Memory (The Physical Layer) Review comment: We should get rid of the rest of this file. Code examples can be developed more for the cookbook. Quick examples can go on the getstarted page. That page isn't meant to teach you everything, just give you a brief idea of what's possible. ########## File path: docs/source/java/modules.rst ########## @@ -0,0 +1,413 @@ +.. Licensed to the Apache Software Foundation (ASF) under one +.. or more contributor license agreements. See the NOTICE file +.. distributed with this work for additional information +.. regarding copyright ownership. The ASF licenses this file +.. to you under the Apache License, Version 2.0 (the +.. "License"); you may not use this file except in compliance +.. with the License. You may obtain a copy of the License at + +.. http://www.apache.org/licenses/LICENSE-2.0 + +.. Unless required by applicable law or agreed to in writing, +.. software distributed under the License is distributed on an +.. "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +.. KIND, either express or implied. See the License for the +.. specific language governing permissions and limitations +.. under the License. + +.. default-domain:: java +.. highlight:: java + +.. _java_modules: + +======= +Modules Review comment: Let's move this page to the top level. We can organize it like https://arrow.apache.org/docs/cpp/overview.html but for Java. How does that sound? ########## File path: docs/source/java/quickstartguide.rst ########## @@ -0,0 +1,482 @@ +.. Licensed to the Apache Software Foundation (ASF) under one +.. or more contributor license agreements. See the NOTICE file +.. distributed with this work for additional information +.. regarding copyright ownership. The ASF licenses this file +.. to you under the Apache License, Version 2.0 (the +.. "License"); you may not use this file except in compliance +.. with the License. You may obtain a copy of the License at + +.. http://www.apache.org/licenses/LICENSE-2.0 + +.. Unless required by applicable law or agreed to in writing, +.. software distributed under the License is distributed on an +.. "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +.. KIND, either express or implied. See the License for the +.. specific language governing permissions and limitations +.. under the License. + +.. default-domain:: java +.. highlight:: java + +.. _java_quickstartguide: + +================= +Quick Start Guide Review comment: IMO this file should just be moved into getstarted.rst -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
